OBJECTIVES: Patient satisfaction with medication is increasingly set as treatment goal because it is hypothesized to increase compliance. This study investigates plausible associations between levels of satisfaction with pain medication and external variables (e.g., satisfaction with medication information, medication characteristics, treatment efficacy as perceived by the patient) as established in the literature; to explore the effect of satisfaction with pain medication on intention to comply with current medication. METHODS: Rheumatoid arthritis (RA) patients undergoing treatment were mailed two sets of questionnaires two-weeks apart: The Pain Treatment Satisfaction Scale, the SF-36, a pain visual analogue scale, and the Brief Pain Inventory. The influence of these variables on satisfaction with pain medication was estimated using structural equation modeling. RESULTS: The population consisted of 68 RA patients with a mean baseline pain score on a one to ten scale of 4.73 ± 2.72. The overall model was significant (chi-square p-value <0.001) with an excellent fit (normed fit index = 0.97). The strongest observed relationship was a positive association between satisfaction with pain medication and intention to take pain medication (unstandardized path coefficient Beta= 0.54, p<0.001). Predictors of satisfaction with pain medication included duration of pain relief (Beta= 0.45, p<0.001), satisfaction with the information provided by health care professionals (Beta= 0.21, p<0.01) and expectations of pain relief (Beta= 0.20, p<0.01). CONCLUSION: RA patients' intention to comply with pain medication is influenced to a large extent by the level of satisfaction with their pain medication. Duration of pain relief positively influences satisfaction with pain medication, as do (to a lesser degree) satisfaction with information about treatment and medication expectations. Improving compliance with care not only depends on the clinical effectiveness of medications, but also on how satisfied patients are with treatment information and how well their treatment expectations are managed.